Gas this happened to you?

Ruby

I’m 35 weeks & 6 days. So I had an orgasm few hours ago I would say like at 1 am, I was fine right after. I just woke up to pee and noticed blood on my shorts, when I wiped there was also blood not heavy but light. Has this happened to you? I’m not having contractions, just lower back pain like period cramps. I’ve had three kids this is my 4th and I’ve never experienced this.